Most security strategies are still utilizing the same approaches to attempt to thwart external threats. Considering the potential dire financial and reputational consequences, it has become quite evident that utilizing the same, inadequate approaches will not improve an organization’s security posture. After all, the definition of insanity is doing the same thing over and over again and expecting a different result.
So, what’s missing? A focused strategy taking into account a human-centric approach.
The industry standard Mitre ATT&CK Framework outlines that not only should security teams be looking for particular behaviors indicative of potential threats, but that teams should also be taking into account how those behaviors should be considered relative to historical activity on that account/device against itself and any other worthy comparisons across the entire organizational estate (i.e., desktops, tablets, laptops and servers, including Windows, Mac and Linux). More importantly, it’s the anomalous behavior associated with users that are the missing element in deciphering these ongoing and everlasting threats.
With technology becoming more accessible and complex in tandem with increased skillsets displayed by hackers, prioritizing a defense against insider threats may be the better strategy. After all, the moment an outsider breaches an organization, they become an insider.
Take the SolarWinds hackers, for instance. Microsoft shared a description of how these hackers were able to avoid detection once inside the systems. By using professional operational security methods and anti-forensic tactics, the hackers remained elusive, leaving minimal footprints while persistently wreaking irreparable havoc. Such behavior is identical to that of malicious inside actors, so it begs the question: If the SolarWinds hackers had been monitored as insiders, could they have been identified earlier in the insider threat attack chain, thereby preventing what’s considered one of the most sophisticated intrusion attacks of the decade?
Common obfuscation tactics can reveal malicious insiders’ disguised intent
Given today’s high-stakes cybersecurity landscape, the growing trend of outsiders becoming insiders can no longer be ignored. Equally important is understanding how exactly insiders work to disguise their malicious intent (i.e. how obfuscation unfolds), because concealing an attack is a crucial step in any successful attack. Once a malicious insider has located the data they want, tested an organization’s defensive measures and collected the desired data, their next step is obfuscation. The good news is, malicious intent is often easier to identify during the obfuscation phase, as many of the activities have no business benefit.
For example, insiders may change file extensions to disguise a spreadsheet, database or document as an image file in order to bypass filters looking only at certain named extensions. They may conduct off-network activity and circumvent organizational VPNs to hide their web browsing activity by clearing cookies and event viewer logs or using stealth browser settings like Incognito mode. Another common obfuscation tactic involves renaming files at an unusual rate, especially when not simply changing a version number. Use of steganography applications based on name, product or vendor ID — even through the browser — and carrying out steganography through command line interfaces.
Behavior profiling and anomaly comparison provide the clearest picture of unusual activity
Ultimately, in addition to being able to recognize common obfuscation behavior and apply that knowledge to reveal malicious insiders’ true intent, organizations need to achieve a holistic, real-time understanding of the intent of each individual user across their organization. Relying on legacy tactics, such as “person of interest” identification or full-time analyst interactions, is simply no longer an option, as such tactics generate too many false positives and degrade endpoint performance. Even more importantly, these legacy approaches do nothing to understand history, trends or context.
Instead, to build the clearest picture of unusual activity, security leaders should consider implementing behavioral profiling and anomaly comparison of insiders. By monitoring employee activity strictly within the guardrails of for-security-purposes-only, organizations can establish a clear baseline of normal, day-to-day behavior for each employee. Anything that deviates from that baseline can then be tracked and escalated if/when it evolves (or risks evolving) into malicious activity. Additionally, the historical anomaly comparison of a multitude of user behaviors can establish an even stronger picture of unusual activity. At the same time, continuously capturing all activity (i.e. activity spanning a variety of data from all endpoints) can provide full visibility into individual users and specific devices across an entire organization.
A real-time, contextual understanding of assets and people is key
To ensure successful insider threat mitigation and management, context is key. Having both an asset-centric and people-centric view of systems, data and machines is critical to gain a proper understanding of context as it relates to insider activities and intent. Furthermore, fully understanding any insider incident requires visibility into the entire attack chain — not just one or two steps — because often, the earlier phases of the attack chain hold the answers to the most important forensic questions.
To keep pace with ever-resourceful hackers and mitigate the risk of devastating attacks like those incurred by SolarWinds, organizations should seize the opportunity to incorporate behavioral profiling and anomaly comparison of insiders into their cybersecurity strategies. By establishing a baseline of normal, day-to-day behavior for each employee without invading personal privacy and taking into account the full context of that data, security teams can gain the power to scalably and effectively identify suspicious behavior before any debilitating damage can be done. In turn, organizations can breathe easier knowing malicious activity will be stopped in its tracks, data loss will be prevented, software investments will be maximized and employees will be protected.